Annex 65, Long-Term Performance of Super-Insulating-Materials in Building Components and Systems. Report of Subtask IV: Sustainability
This report of the International Energy Agency (IEA) Annex 65 subtask 4 considers a few selected but relevant means of assessing the current sustainability performance of Super-Insulating Materials (SIMs) namely the Life Cycle Assessment (LCA), the Life Cycle Cost calculation (LCC), and the Embodied Energy (EE). Subtask 4 of IEA Annex 65 investigated the existing studies on LCA on super insulation materials (SIMs), according to the product categorization agreed by the Annex. After mapping the current state, the subtask constructed a life cycle inventory (LCI) of SIMs to make a transparent assessment of the environmental performance of a range of SIMs. Based on this LCI, a life cycle impact assessment (LCIA) of SIMs was also conducted. Contribution analysis was conducted to highlight the hotspots of the environmental performance of SIMs and a comparison between the conventional thermal insulation materials is shown. The SIMs examined in IEA Annex 65 are advanced porous materials (APMs) and vacuum insulation panels (VIPs).
The original approach of this subtask was to construct this transparent LCI through cooperation with the manufacturers. However, this approach was unable to be implemented due to various challenges including resolving concerns over confidentiality issues. This led the subtask to develop the LCI based on the existing literature.
The LCIA of VIP showed a good level of coherency with the published Environmental Product Declarations (EPDs), which normally does not contain transparent LCI information. The result creates a solid basis for the comparison with conventional insulation materials for other LCIA studies.
Meanwhile, the LCIA result of aerogel (the APM examined) showed a large difference between published EPDs. This was due to the fact that the available LCI information only represented the pilot scale. Although EPDs represent product-specific LCIA results, the level of information described in the document may not always be sufficient to allow a fair comparison. This lack of transparency remains a challenge for new advanced materials.
A hypothetical case of renovation which looked into the economic and the environmental payback time showed that SIMs have very long simple payback times in most northern European cities. However, places with high land price or high heating demand can affect the competitiveness of the SIMs, both economically and environmentally. In reality, there are various limitations that may affect the decision of insulation material selection. Cases where space limitations are given, or preservation of the architectural design were seen as reasons for implementing the SIMs in the existing building renovation projects.